KAGRA SCIENTIFIC CONGRESS: COLLABORATORS’ INFORMATION EXCHANGE

2020/APRIL 17

KSC Newsletter
Issue 7KAGRA entered the observing mode!
We are operating at Mpc-level finally
After we signed to the memorandum of agreement (MoA) [JGW-M1910663] [JGW-M1910664], with LIGO/
Virgo in October, our target has been concentrated to join to Observation 3 (O3) of LIGO/Virgo. The
requirements [JGW-M1910813] are to improve the sensitivity of the detector over 1 Mpc in binary neutron-starrange, and to clear the readiness checklists of data flows/calibrations/organization. When we first locked thedetector on August 23, 2019, the sensitivity was 0.4 kpc. In order to reach our target (10 Mpc), the team so far
made great efforts for commissioning and noise-hunting.
The planned date for starting observation was postponed acouple of times. We made engineering run in December,then went back to the commissioning. After the announceof the first lock of the power recycling system on January
26 [klog12639] and OMC readout ready [klog12763],
our sensitivity started recording the number as wegraphed below.
We declare the start of the observation on February 25
with around 300 kpc level. The team decided to go back tocommissioning to try again with the signal recycling
The current record of the sensitivity is 970 kpc on March
configuration. We heard we momentally locked with dual 29, 2020. [klog 13840]
recycling, but not enough stability for observation.
Since our time was limited and we decided to go into theobserving run from April 7 for two weeks. However, the new virus COVID-19 changed the situation. Both LIGO/
Virgo had to stop their detector from March 24. On April 3, KAGRA proposed to make a joint observation with
GEO600 in the framework of LVK network, and core members are discussing details with GEO.

Reported records of the sensitivity in binary neutron-star range(in kpc).

The moment of declaring the start of observation on February
25, 2020. [Photo from KAGRA webpage]1

KAGRA Scientific Congress Newsletter No. 7

Directions

2020 APRIL 17

Thanks for your patience, LV colleagues

All of KAGRA members have been accelerating for joining O3. However, we have faced many issues in our
preparation processes.
For example, when our data analysis groups tried to join the parameter estimation rotation (PE rota), which
is a sort of "shift" participation of running cluster machines, it turned out we need authentication of our group
to login to LIGO clusters. We (acutually, Hirotaka Takahashi, who is in charge of Identity and Access
Management) consulted GakuNin (Academic Access Management Federation in Japan). GakuNin found this is
the first such request from a research project (not from a university unit), and we had to wait until GakuNinchanged their official rule, and it realized in the end of February.
The official monitors of the GW network, gwstatus (below right) and gwistat, are now showing the realtime status of KAGRA (actually with 30 sec delay). An iOS & Android application of GW event list, Chirp is also
showing the real-time status of KAGRA. All of them were implemented along to our requests, and somebody in
LV kindly responded promptly.
Our announce of the starting day of the observation to LV colleagues was initially “from December”. The
schedule changed to “the end of January”, then to “the end of February”. Every Wednesday early morning,
Kajita-san and I report the status of KAGRA at the LVK management call. Though we had to report the delay
repeatedly, LV colleagues gave us always gentle, generous, and supportive reactions.
Up to now, we owe much in technical helps by LV colleagues. We appreciate on these helps honestly, andshall give back to them with our scientific contributions.
Hisaaki Shinkai 🍏https://monitor.ligo.org/gwstatus
now shows the status of KAGRA also.

Collaboration

Shinji Miyoki(from web)

New Project Manager and new SEO
Due to the retirement of Yoshio Saito (ICRR) from the project manager (PM) [see page10], the executive office (EO) decided Shinji Miyoki (ICRR) for the next PM. Shinjiorganized new System Engineering Office (SEO) members as follows (alphabeticalorder):
Masaki Ando (U Tokyo)
Keiko Kokeyama (ICRR)
Yoichi Aso (NAOJ)
Osamu Miyakawa (ICRR)
Tomotada Akutsu (NAOJ)
Hideyuki Tagoshi (ICRR)
Nobuhiro Kimura (KEK & ICRR)
Takashi Uchiyama (ICRR)
The KSC newsletter asked Shinji for some comments, but could not receive any response.
He might be tooo busy now.

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KAGRA Scientific Congress Newsletter No. 72020 APRIL 17

LVK collaboration
Along to the works with LIGO/Virgo, we established two new groups. One is the committee of climate change:
Luca Baiotti (Osaka U, Japan) and Quynh Lan Nguyen (U Notre Dame, USA). The other is the KAGRA-EPO(Education and Public Outreach) group: Heather Fong (RESCEU, Japan), Albert Kong (NTHU, Taiwan), Kwan
Lok Li (NTHU, Taiwan), Wei-Tou Ni (WIPM, China), Quynh Lan Nguyen (U Nortre Dame, USA), Yoshihisa
Obayashi (ICRR, Japan), Kuo-Chuan Pan (NTHU, Taiwan), Lijing Shao (Peking U, China), Hisaaki Shinkai (OIT,
Japan), and Leo Tsukada (RESCEU, Japan). Both are consists from all self-nominated members.
The making the committee of climate change was upon a strong request from LV, and its tasks are introduced by
Luca’s article below. The KAGRA-EPO will coordinate the joint EPO works with LV, and also try to approach to
public with original idea in coordination with the public relation team of ICRR. We know many of us are
participating outreach events officially and/or personally. Heather gives us her wishes to make gravitational
waves.

CCC

LVK Committee on Climate Change
Luca Baiotti (Osaka U.)

In these days, the pandemic is what attracts all the attention, but in the longerterm future the issue and implications of climate change will probably be much
more important for human society. After a spontaneous lunch-time discussion on
this topic within a group of LSC members, Steve Fairhurst and Patrick Brady
suggested to start a working group to evaluate LVK activities in light of climatechange. Many scientific institutions already have working groups and declarations
on the issue, including CERN, Fermilab, the American Astronomical Society, andthe astronomy community in general (see, e.g., https://arxiv.org/abs/
1910.01272v1).
As a first step a (yet informal) LVK Committee on Climate Change was created,with Daniel Holz as chair. The committee currently has more than ten members,
including a few from Virgo and Quynh Lan Nguyen and myself for KAGRA. A request of formal recognition has
been forwarded to the LVK leadership some time ago, but the official approval has not come yet, probably
because of the many more urgent matters that are flooding us in this period.
The goal of our Committee on Climate Change is to examine the collaboration’s carbon footprint and identify
potential steps to mitigate our impact. We also hope to contribute to build awareness of this critical topic, bothwithin and outside of the LVK collaboration. We have started gathering information mainly about 1) how much
power our interferometer sites and our data-analysis computer systems use, 2) how much of the electricity weuse is already produced in sustainable ways, 3) what has been the impact of construction of ourinterferometers, 4) how big is the environmental impact of travel to meetings specific to the wholecollaboration or to the individual detectors.
After analyzing our findings, we plan to come up with some recommendations to reduce the LVK collaboration
impact on climate change. We will also propose a public statement to be put on our websites, declaring that the
LIGO, Virgo, and KAGRA Collaborations acknowledge the scientific consensus regarding the existence of climatechange, as well as the dangerous impact of greenhouse gas emissions from human activity. Hopefully thestatement will continue with a list of action items we have implemented to mitigate our contribution toenvironmental problems.🍏

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KAGRA Scientific Congress Newsletter No. 72020 APRIL 17

EPO

What made you decide to study gravitational waves?
Heather Fong (RESCEU, U. Tokyo)
We all have an answer to that question, answers as varied and unique as we are toeach other. But our answers probably stem from similar roots: opportunity andpassion. Opportunity is how we got into the field in the first place, while passion is
why we stay. In Education and Public Outreach, our goal is to engage the public byfinding fun and creative avenues for them to engage with us and our research, and toshare our excitement for gravitational waves, physics, and science.
There are many excellent ways to do outreach, and the
aspect I am most passionate about is education. During
graduate school, I worked closely with the outreachteam at the University of Toronto's Dunlap Institute for
Astronomy and Astrophysics with the focus of reachingout to educators. We learned that while educators are
excited to introduce modern physics into their lessonplans, the time and effort required to present suchconcepts both creatively and accurately is often an
overwhelming task. As a result, our goal was to create
lab experiments that taught astrophysical phenomena
such as black hole lensing and planetary transits, while
also ensuring they could be easily recreated in aclassroom and facilitated by the educators themselves.
Our target audiences included elementary, junior, andhigh school students, where we focused not only thephysics itself but also on critical thinking and peer
collaboration. I also developed a few activities thatwere gravitational wave-specific, which have been wellreceived by educators and students.
It is my hope that through KAGRA EPO, we
can continue to connect with the public,
whether through social media, public talks,outreach events, or engaging them inclassrooms. In particular, I look forward tobringing some of the activities that have beendeveloped and improving them so they canalso be made accessible by eager minds on
this side of the globe. For me, outreach iscreating a ripple in hopes that it will one day
turn into waves - new physicists and science
enthusiasts, who will continue to add to ourunderstanding of the universe.🍏

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KAGRA Scientific Congress Newsletter No. 7

Pandemic

2020 APRIL 17

COVID-19 in the world

Honestly speaking, when we celebrate the new year 2020, nobody could imagine of this world-wide newcorona-virus COVID-19 pandemic. The tragedy was first reported as the lockdown of Wuhan China late
January. The growth of the number of infected people (and death) are never stopping until now, and wealready heard over a million people in the world have been infected. Almost all countries stop to move people
between countries or even between cities. Almost all meetings are cancelled. Most universities stop to givelectures in person. We do not know when this situation ends. Our colleagues are kindly reporting the on-goingsituation each region.
In February, the situation in China was extremely bad. About 80,000 people was infected.
Now the situation has become much better. Averagely, 30 infected people are reported.
Usually all of them come from aboard.
China
Regarding to people's daily life, many factories have return usual working status. But most
schools and universities are still closed. Only online teaching is going on.
For our researchers, we do study as usual. The only difference is working place changes tohome and online discussions become much more popular and frequent. The KAGRA colleagues in China areclosely following the development of KAGARA detector. We are happy to see the horizon for BNS is now about

Zhoujian Cao 🍏 (April 4)

1Mpc.

TaiwanIn Taiwan even though our life is as usual as past, to fight against COVID-19, several
enforcements are applied inside the campus. First, everyone needs to have the bodytemperature measurement every day. Then, a sticker will be attached to those who havenormal temperature; in case of abnormal temperature, the guy will be prohibited to enter thecampus immediately and reported to the Campus Security Office. Before entering theclassroom, office, or laboratory, you need to scan the QR-code as a registration. It
is advised to wear a sanitary mask when taking the school bus. Let us win thisRay-Kuang Lee 🍏 (April 12)

battle soon.

Courtesy: NTHU website

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KAGRA Scientific Congress Newsletter No. 72020 APRIL 17

April is the beginning of a flower blooming season in Korea. However, social distancing
became a new normal and our work/life changed a lot this spring. Followed by cancelation of
graduation ceremonies in late February, almost all student gatherings, academic events have
Korea
been canceled or postponed. Dorms are closed. Campus is open with some restrictions. Not
only students, but those affiliated in universities and research institutions are strongly
encouraged to work from home whenever possible.
March was in particular hectic as public hygiene protocols and social distancing policy at universities had to be
updated almost daily in order to cope with the national-wide situation. Since April, things seem to be slowly
under control – at least in campus. Many pre-cautions have been in practice such as wearing a mask in campus,
hand sanitizers at every corner in a building, and most recently, anti-virus films on elevator buttons !
An academic year at universities in Korea begins from the 1st of March, but this year, it has not begun until
mid- or late-March. Moreover, all university lectures are given online. Ewha Womans University recently
decided to make the 2020 Spring semester be completely online. Offline lectures/exams/practicum are to be
refrained. Online lectures are challenging but doable. How to evaluate students is another challenge ahead ofus. In fact, younger generations in Korea are accustomed to study online through the Korea Educational
Broadcasting System since young age but many of them are not used to take exams online. It is curious if thispandemic would have some good impacts for higher education in Korea in the long run.
Not only educational institutions, academic organizations have difficulties to cope with the COVID-19
pandemic. Most academic events are canceled or postponed. The Korean Astronomical Society’s Spring Meetinghas been canceled and the 2020 Korean Physical Society Spring Meeting is postponed to July in the city of
Changwon. I hope things will go back to normal soon and all can meet at KIW7!

Chunglee Kim 🍏 (April 12)
Newly Joined

GW experiment group at KASI

Sungho Lee

Greetings from the GW experiment group at Korea Astronomy and Space Science Institute (KASI), Korea. Thesedays we always wear masks at work to protect each other, but it was excused for a second for this photo. One
member of our group is working at home remotely to avoid risk of infection on the commuter train. We hopethat the COVID-19 situation ends soon and we can start participating in the squeezing experiment at TAMA300
and other activities for KAGRA improvement. In the meanwhile, we have been building a squeezer at KASI witha goal to complete an initial setup in this year.

Photo taken on 7th, April, in front of Eun
Ha Su hall which means the Galaxy hall.
From left to right: Yunjong Kim, ChangHee Kim, Jinwha Gene, Sungho Lee, Jae
Sok Oh, Jeong-Yeol Han, Hyeon Cheol
Seong, and Ueejeong Jeong in the left
box. Three members have newly joinedsince the last F2F meeting in Toyama;
Ueejeong (electronics engineer) from thisyear, Jinwha (laser expert) and Jae Sok(optomechanical engineer)from this month.

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KAGRA Scientific Congress Newsletter No. 72020 APRIL 17#iorestoacasa (I stay at home) is the hashtag that summarizes the actions of the Italian
government and the new lifestyle that Italians are living where everything that is notessential is closed and the days of rush are only a memory. Suspended in a sort of glass
Italy
snowball, people found a new equilibrium. After one month of complete lockdown, people
rediscovered the meaning of family, how to stay with children all day or how to stay alone,they understood how to organize their jobs at home (often with unexpected positive results)
but more important they learnt what is essential for their life.
Never before people seek human contact, talk to each other, try to feel part of a community like now: very often
Italians organize flash mobs on the balcony to sing a song all together or organize skype calls for a birthday orzoom calls for an online aperitif. People are cooking together rediscovering the slow gestures of tradition not
only to prepare food but to reaffirm life.
Today is Easter, a religious holiday where people used to be together with their families but this year's leitmotiv
is "we are far away today to be able to return to embrace tomorrow". This concept is reaffirmed by Catholic
Church showing the Pope alone in San Pietro or concerts in empty churches broadcast online only.
In parallel there is an Italy that is working hard to aid in this situation. Doctors, nurses and medical staff risk
their lives every day to fight the virus (more than 100 doctors died helping people). Alongside them, there arethousands of volunteers, civil protection and even fashion firms (Gucci, Prada, Bulgari) that have changed theirproduction to manufacture masks, white coats, sanitizing gels or Ferrari and FCA who are producing
respirators. Universities and schools are open but in remote, people are working a lot for keeping lectures andexams online with a strongly positive reaction from students… a strong signal for future generations: we keep
going even in this dramatic situation.
To help, the best thing right now is to stay home. On this principle, EGO/Virgo site was closed: “The O3b science
ended Friday, March 27, 2020 at 5 PM UTC. From Tuesday 31st onwards the interferometer will be kept as much as
possible in a standby state with the goal of being able to come back in operation as soon as external condition willallow for it and also to minimize the risk of damage”. AdV+ upgrading activities are almost completely
suspended because the companies that have to produce mechanical, electrical or optical parts are closed. In
meanwhile, the organizational part is moving forward with more force than ever. The review of subtasks istaken advantage by all data collected up to the last day and reports on technical noises. Decisions are madeweek by week in order to follow the progress of the health situation.

Flavio Travasso 🍏 (April 14)

The Spanish government declared the state of emergency on March 15th and we have been
staying home for a month. As you may know, hospitals went overcapacity here in Madrid andI read a lot of sad news related to it.
Spain
People are not allowed to walk outside for non-essential and non-urgent reasons. There arevery few people in the streets and police are patrolling around to check on people and fine
who violates the rule. The city looks empty as in some post-apocalyptic movie. I never
expected to see it for real.
All people stopped working except in hospitals, supermarkets, and pharmacies. Universities and research
institutions are all closed. Researchers in my institute try to keep up research activities by organizing Zoom
meetings, while personally, it's difficult to work at home with a small child as kindergartens are also all closed.
The situation of being in quarantine is psychologically tough for both child and parents. But at the end of a longday, we join people coming out to balconies and give our applause for the doctors and nurses working in
hospitals. My child learned to clap his hands and enjoys interacting with neighbors by waving his hand. I see
people are enduring even in this difficult period.
The rumor says that the state of emergency will be extended at least until early May, while essential activities
resumed today (April 13th). Probably it will take more for research activities to get back to normal. I hopeeveryone in the collaboration is safe. Please stay healthy and don't forget to cheer up yourself and your dearest!

Sachiko Kuroyanagi 🍏 (April 14)
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KAGRA Scientific Congress Newsletter No. 72020 APRIL 17

It has been a month since the coronavirus outbreak in the US and all the classes at mostcolleges has moved to distance learning in the middle of March. I came to University of Notre
Dame campus the day after Easter holidays; the campus was unusually quiet, I can hear theUSAwhisper of the spring during the virus pandemic, our college lives are still going on. We are
not able to go to the front-line as health workers, but we help in small ways. We work athome to reduce spreading the virus, yet keep our daily schedule the same. Remote classmeeting times are the same as the in-person classes before Spring break. Academic activities,
colloquia, “Astro-ph” meeting, informal lunches, pedagogy coffee discussions, research group meeting, are alldone through Zoom, but they still go on. Those activities not only keeping us motivated during the “stay athome” period but also help us reaching out to each other to know that everyone still safe and stay well. At thismoment, most research labs are suspended to be extra safe, however, students can defend still their thesis
remotely as many students at the Department of Physics have completed their Ph.D. defense or Ph.D. candidacy
exams. Atul Kedia, who is working with Prof. Grant Mathews on simulating binary neutron star mergers using
the Einstein Toolkit code for to test different nuclear equations-of-state, completed the Ph.D. candidacy on April
6th. Atul had to give a half-hour talk on his research, as well as proposed research for the next few years. The
talk is followed by questions and answers from the four professors on his committee. Given the COVID-19
concerns, his candidacy exam was done completely online. This type of research work is continuing almost
normally as all codes of mergers are run on the Center for Research Computing machines at Notre Dame, which
gives us easy remote access. I attended the program “Lighting new Lampposts for Dark Matter“ at Simons
Center for Geometry and Physics in New York, where the coronavirus hit the hardest. I was there just before theoutbreak and we practiced social distancing during our meetings and discussions to maintain safety foreveryone. A week later, all in-person activities stopped due to the outbreak of the coronavirus. Despite the fearof the inviable virus and the sadness of those who suffered or passed away, for me, I am thankful to the ICRR’s
Inter-University Research program. I am particularly thankful my daily life can happily continue; my son studies
from home with me; and my puppy is so joyful when we stay home all day.
Quynh Lan Nguyen 🍏 (April 15)

Image: Notre Dame Golden Dome (taken by Quynh Lan on April 14, 2020)

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KAGRA Scientific Congress Newsletter No. 72020 APRIL 17

Prime Minister Abe spent a month to change a law
in February and March, and finally made adeclaration of "Emergency Situation" on April 6
JAPANaround Tokyo, Osaka, and Fukuoka. Governors ofeach prefecture closed all the public schools for amonth and are suggesting people for refraining
from going out. PM Abe also announced that the
government will distribute two masks to each family on the April
fool's day. It turned out not a joke, and people understand that the
keyword of the Abe administration "Abenomics" (Abe+economics) for
past 7 years has been changed to "Abenomask".
Most of us (researchers) are staying home and keep discussion
online.
Kamioka is one of the safest places in Japan. No infected person has been reported in Hida
City as of April 17. However, as the University of Tokyo raised its activity restrictions1 tolevel 3 (maximum restrictions) on April 8th and as the number of infected people in Toyama
City, where many KAGRA onsite people are commuting from, are rapidly increasing from the
beginning of April. In addition, the main road from Toyama city is blocked due to landslide and hard to accessto Mozumi from Toyama city.

Kamioka

1The University of Tokyo' s activity restrictions index for preventing the spread of COVID-19 is found athttps://www.u-tokyo.ac.jp/content/400137605.pdf

As we all received a message from PI on March 24 [kagra 03424], the KAGRA Observatory
will follow the guideline of the Japanese government on COVID-19. Kajita-san wrote to us,
KAGRA“If we have even a single personnel, including a visitor, who is infected by COVID-19 in the
KAGRA Observatory, the KAGRA Observatory and KAGRA itself will be closed immediately.
The health of our colleagues is the top priority.”
KAGRA Observatory decided to apply almost the same restriction as the university's Tokyo and Kashiwa
campuses from April 13th. We consider KAGRA's observation as one of “currently conducting long-term
experiments that would experience a significant loss to their research if stopped,” and hence we operate theobservation with minimum researchers, technicians and administrative staffs living in Kamioka or Toyama. In
addition, we require to wear a medical mask in the control room and wash hands frequently to prevent
infection in the KAGRA Observatory from an asymptomatic infected person.
KAGRA is currently in operation. Under such situation, the collaborator-shift schedule was almost cancelled
after mid March, and all shifts are taken only by local KAGRA colleagues. In addition, in the evening of April
16, Japanese government decided to declare the state of emergency for whole country, which suggests people
not to make unnecessary movement until May 6. We once discussed a possibility of the extension of ourobservation period after April 21, but it will be quite unlikely to do so except some necessary calibration works.
Hisaaki Shinkai & Yoshihisa Obayashi 🍏 (April 17)

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KAGRA Scientific Congress Newsletter No. 7

Retirement

2020 APRIL 17

Yoshio Saito, Project Manager for 7 years

Professor Yoshio Saito took the position of the project manager (PM) of KAGRA April 2013, when theconstruction of KAGRA tunnel was in the halfway. From April 2014, he became a permanent resident ofKamioka, and has been at the forefront of the KAGRA construction period, which began with the installation of
the vacuum equipment. As PM for seven years, KAGRA has come to the place where gravitational wave
observation can be performed with an observation range of almost 1 Mpc.
Prof. Saito underwent surgery twice while staying in
Kamioka. In particular, the surgery in February 2018 was a
big one. I went to visit the hospital and gave him aphotobook of minerals and an idol group's yearbook.
Professor Saito smiled after seeing what I chose, but I
could feel his pain after the operation. After leaving the
hospital, Prof. Saito gave me a gift in return. It was a great
picture book that introduces the world's famous dishes
that can be enjoyed with children.
What amazes me, Prof. Saito has wide range of knowledge
and curiosity. Not to mention the specialized vacuum andphysics, but also mathematics (with its history), chemistry,
insects (he stuffed the wasps), world history, languages(French, Chinese, Korean), music (he played piano),cooking, photo, cycling, collection of picture books, andeven the much knowledge of actresses and idols. He is
also really familiar with Yakamochi Otomo (大伴家持), a

Latest ICRR NEWS featured KAGRA, and provides
long interview of Prof. Yoshio Saito.

Japanese statesman and Waka poet in the Nara period. I
heard he traveled along the path followed by Yakamochi
Otomo in Toyama area. In this way, Prof. Saito was thewalking encyclopedia and knowledge giant for me.

Prof. Saito retired from PM at the end of March 2020, but heis planning to stay in Kamioka for some time. Even now, heworks in the analysis building at Mozumi. We are currently working on the design of the vacuum equipment,
which is needed for seeing the surface of the beam splitter in a vacuum. I see every day he draws blueprints
using graphing tools on graph paper. When the mess of the coronavirus has subsided, Prof. Saito will return to
Tsukuba, then will continue to work at the ICRR Kashiwa as a member of KAGRA. KAGRA is still a developing
project. I would like to keep asking Prof. Saito for advice based on his deep experience.
Professor Saito, Thankyou for your hard work.
We appreciate you foryour long contributions.

Takashi Uchiyama 🍏
Office of Prof. Saito. Many drawings on the board.

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KAGRA Scientific Congress Newsletter No. 7

Previous F2F

2020 APRIL 17

The 24th Face-to-Face meeting at RESCEU, December 4-5, 2019
Program: http://gwwiki.icrr.u-tokyo.ac.jp/JGWwiki/LCGT/Meeting/f2f/2019Dec

The group of Research center of the Early Universe (RESCEU) Univ of Tokyo hosted our F2F. A day before, December
3, the data analysis groups organized a satellite meeting, where we discussed checking lists for joining O3. The
December F2F meeting was for two days as always, and we had meeting dinner at the very standard drinking
restaurant at Ueno. We had 110 participants, 6 doctoral thesis talks, 15 thesis related poster presentations. Poster
awards were to Yutaro Enomoto and to Toshiya Yoshioka [see p. 12]. We thank Jun’ichi Yokoyama and RESCEU
members for your kind hospitality. 🍏

Cancellation & Postponement* LVK meeting March 2020 was organized in telecon style.
* Face-to-Face meeting April 2020 at ICRR Kashiwa was cancelled.
* KIW7 at Taiwan in May 2020 was postponed to December 2020.
LIGO-Virgo collaboration (LVC) meeting was held in March and September every year, and the series hadchanged the name to LVK collaboration meeting from March 2020. However, due to the pandemic of COVID-19,
the meeting was announced to be held in remote in early March. We now knew this was the right decision.
People in the world are trying not to meet in person for avoiding infections. This situation is supposed to be
kept for next months also.
In such situation, we cancelled our Face-to-Face meeting April 2020 which was planned to be held at ICRR
Kashiwa. (We instead will have telecon May 27 and 28.)
National Central University group (head: Yuki Inoue) in Taiwan
announced once to host the 7th KAGRA international workshop(KIW7) at the end of May 2020. However, they postponed to holdit in December, 2020. The season is overlapped with December
Face-to-Face, so that the board is planning to have F2F also at NCU
the day before. NCU group plans to provide remote access. The
board thanks the hosting groups of KIW8 (Sungho Lee, KASI,
Korea) and KIW9 (Hong-Bo Jim, NAOC, China), for agreeing therelated shift of the schedule.

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KAGRA Scientific Congress Newsletter No. 7
Poster Award

2020 APRIL 17

We awarded Toshiya Yoshioka and Yutaro Enomoto for their poster presentations at the 24thFace-to-Face meeting at RESCEU, U. Tokyo, December 2019. Congratulations! Here is the abstractof what they did.

Development of Intensity Stabilization System for Laser in KAGRA
Toshiya Yoshioka (Laser Phys. Lab., U. Toyama)
Reduction of the laser intensity noise would be crucial for the observation of thegravitational waves, which are extremely tiny signals. The laser intensity noise
directly fluctuate the output signals and this cannot be distinguished from theoriginal signal due to the gravitational signal. For high power laser, a random driftof the test mass caused by the radiation pressure of the intensity noise can be
another indistinguishable noise. Therefore, we developed and installed theintensity stabilization system(ISS). This system is based on the feedback systemusing an acousto-optic modulator (AOM) as an actuator of the laser intensity
modulation. In this system, the laser intensity noise can be reduced as follows:
power of a part of the laser beam is monitored by a photo diode(PD). Then the
output signal from the PD is compared with a DC stabilized reference voltage
and the differential signal between them is feedbacked to an AOM placed
upstream the laser beam. We designed the electric control circuit so that the
response of the whole system should be stable, the unity gain frequency should
be as high as possible and the phase margin should be greater than π/6. For the
ISS installed in KAGRA, the AOM is placed near the exit of the main-laser output
in the pre-stabilized laser room, the output beam transmits two mode cleaners:
a premade cleaner and an input mode cleaner, and then a PD monitors thepower of the laser beam transmitting the 1st input mode matching telescope
mirror. Although the monitored noise level was unexpectedly as high as 10−4/√Hz, whose sources have not yet been understood, our system successfully
reduced that by about 3 order of magnitude to below 10−7/√Hz in thefrequency range between 25Hz and 5kHz. As the results, the sensitivity of differential mode of arms (DARM) is
improved by one and a half order of magnitude in the region above 60 Hz as shown in the Figure.🍏

Interferometer Locking Scheme for Advanced
Gravitational-Wave Detectors and Beyond
Yutaro Enomoto (U. Tokyo)
Among the lock acquisition process, achieving the resonances of the arm
cavities is particularly challenging because kilometer-long arms make theirlinewidths narrow. In the third generation detectors, which will have longer
arms with narrower linewidth, the lock acquisition process will be even morechallenging. In lock acquisition of Advanced LIGO, a scheme called arm lengthstabilization (ALS) has been used, where auxiliary lasers having different
wavelength than that of the main laser sense the arms independently.
However, it is not trivial to scale up the system of Advanced LIGO due to its
configuration.
In this study, a new type of the ALS system was designed and implemented in
KAGRA; the system is designed to be compatible to the third generation
detectors. The system satisfied the requirement of KAGRA so that lockacquisition of the Fabry–Perot Michelson interferometer of KAGRA wasachieved with our system. The study also discussed potential issues and R&D
items in applying the system in the third generation interferometer,
proposing a new lock acquisition scheme with a sub-carrier field.🍏

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I II

III

IV

V

VI VIIVIIIIXKAGRA Scientific Congress Newsletter No. 7
Poster Award

2020 APRIL 17

At the 29th JGRG workshop in Kobe University, November 2019, Mei Takeda was awarded oneof the poster award. Congratulations!

Data Analysis of Gravitational Waves from the SASI mode in a corecollapse supernova with the Hilbert-Huang Transform
Mei Takeda (Niigata U. M2)
We have proposed the effectiveness of Hilbert-Huang Transform (HHT) foranalyzing a GW from standing acceleration shock instability (SASI) in corecollapse supernovae (CCSN). The explosion mechanism of CCSN is unclear.
However, some numerical simulations suggest that SASI might play a crucialrole in it. It is important to investigate whether SASI actually occurs, andGWs could be a smoking-gun signature of the SASI.
For these analyses, a time-frequency analysis method is usually used, which
determines the base waveform in advance and expresses the original signal
by superimposing it. However, it is difficult for these methods to treat thefrequency of the non-stationary signal as a function of time. The frequencyof the SASI mode retains the internal information of the star before theexplosion, and detailed analysis will lead to its understanding.
We turned our attention to HHT. HHT decomposes a signal as asuperposition of intrinsic mode functions (IMFs) whose amplitude andphase change over time. Since the waveform of the IMF is determined
adaptively to the signal, it includes the possibility of directly extracting the physical mode. In addition, the frequency
is defined as the time derivative of the phase for each IMF.
As a result, we clearly extract the SASI mode from a simulated GW and statistically evaluate the frequency
characteristics. As future work, we will analyze the signal superimposed on simulated and real detector noise.

PhD Thesis

The list of theses are available from our wiki,
http://gwwiki.icrr.u-tokyo.ac.jp/JGWwiki/KAGRA/Publications#PhD
The KSC newsletter asked successfully defended persons to introduce their thesis here.
Dr. Enomoto is the first one to appear.

Interferometer Locking Scheme for Advanced Gravitational-Wave
Detectors and Beyond
Yutaro Enomoto (U. Tokyo)
In this study, a new type of the ALS system (green-locking system) was designed andimplemented in KAGRA; the system is designed to be compatible to the third generation
detectors. The system satisfied the requirement of KAGRA so that lock acquisition of the Fabry‒
Perot Michelson interferometer of KAGRA was achieved with our system. The study also
discussed potential issues and R&D items in applying the system in the third generationinterferometer, proposing a new lock acquisition scheme with a sub-carrier field. Please also
refer to the article on the Poster Award.
(Ph.D., The University of Tokyo, March 2020,
Supervisor: Masaki Ando)

13

KAGRA Scientific Congress Newsletter No. 72020 APRIL 17

WE HEAR THAT …
Jun’ichi Yokoyama (RESCEU) received award from Minister of MEXT (see p.15)
Simon Zeidler moved from NAOJ to Rikkyo University as an assistant professor, April 2020.
Takafumi Ushiba moved from ICRR Kashiwa to ICRR Mozumi as an assistant professor, Feb. 2020.
Tatsuya Narikawa moved from Kyoto Univ to ICRR as a PD researcher, April 2020.
Nami Uchikata moved from Niigata Univ to ICRR as a PD researcher, April 2020.
Masayuki Nakano moved from University of Toyama to ICRR Mozumi as a PD researcher, April 2020.
Soichiro Morisaki graduated Univ Tokyo and moved to ICRR as a PD researcher, April 2020
Koseki Miyo graduated Univ Tokyo and became a PD researcher, April 2020
Yoshihisa Obayashi moved from ICRR Kashiwa to ICRR Mozumi, April 2020.
Shinya Funada moved from University of Toyama to ICRR Mozumi, as an assistant manager, April 2020.
Eri Sakamoto moved from NAOJ office to ICRR Mozumi office as a secretary, April 2020.
Congratulations! If you have other news, please notice them to the editors.
Yayoi Hara, ICRR Mozumi office, retired at the end of March 2020.
Yukari Maeda moved from ICRR Mozumi office to Super Kamiokande office, April 2020.
Koki Okutomi moved from ICRR Mozumi to a company in Tokyo, April 2020.
Ayako Ueda, KEK technical support staff, retired at the end of March 2020.
Kyoichi Takayama moved from ICRR Mozumi office to Univ Toyama office, April 2020.
We miss you. Thank you for your long contributions for the KAGRA collaboration.

NEW COLLABORATORS (*=NEW GROUP)

Rikkyo University, Experimental Group*
Simon Zeidler (Assistant Professor)
Shanghai Astronomical Observatory
Gang Wang (Assistant Professor)
Tamkang University
Hong-Yu Chou (Graduate Student)
Hui-Chih Huang (Graduate Student)
The Chinese University of Hong Kong
Tsz Lok Lam (Graduate Student)
The Institute of Physical and Chemical Research(RIKEN)
Shigehiro Nagataki (Chief Scientist)
Tetsuo Hatsuda (Program Director)
Yongjia Huang (Graduate Student)
The University of Tokyo, Institute for Cosmic Ray
Research (ICRR), Kashiwa
Masaki Iwaya (Graduate Student)
Takumu Sugiyama (Graduate Student)
Ryouta Suzuki (Graduate Student)
The University of Tokyo, Institute for Cosmic Ray
Research (ICRR), Mozumi
Shinya Funada (Assistant Manager)[December 2019 — April 10, 2020]
Academia Sinica
Feng-Kai Li (Research Assistant)
Cheng-Yi Chiang (Graduate Student)
Hsiang-Yu Huang (Graduate Student)High Energy Accelerator Research Organization (KEK)
Shinichiro Michizono (Professor)
Hirotaka Nakai (Professor)
Norihiko Kamikubota (Professor)
Yasunori Tanimoto (Associate Professor)
Hirotaka Shimizu (Assistant Professor)
Korea Astronomy and Space Science Institute (KASI)
Ueejeong Jeong (Researcher)

Nagaoka University of Technology
Saki Kobayashi (Graduate Student)
Kohei Shiota (Graduate Student)
L. Malith M. De Silva (Graduate Student)
National Central University
Hong Lin Lin (Graduate Student)
National Taiwan Normal University
Jie-Shiun Tsao (Graduate Student)
Osaka City University
Mei Takeda (Graduate Student)

14

KAGRA Scientific Congress Newsletter No. 7
Awarded2020 APRIL 17

Minister of MEXT Award to Jun’ichi Yokoyama

On April 7, Ministry of Education, Culture, Sports, Science & Technology Japan(MEXT) announced the Minister Award1,2 this year. Among the 50 recipients of
Research Section, Jun'ichi Yokoyama (RESCEU, Univ Tokyo) is listed together withhis colleagues Masahide Yamaguchi (TITech) and Tsutomu Kobayashi (Rikkyo Univ)
for the work on the most general model of inflationary universe.
Jun'ichi told us, "This is for the proposal of the Generalized G-inflation which isan inflationary universe model that includes practically all the single-field inflation
model, but it is quite relevant to gravitational wave science, as our formula oftensor perturbation, in particular the expression of the speed of gravitational waves
in modified gravity theories, has been used to constrain theories of gravitation
using the observation of GW170817.”
Congratulations!!
1 https://www.mext.go.jp/b_menu/houdou/mext_00187.html
2 https://www.jps.or.jp/information/2020/04/reiwa2monka.php

0 thIt’s a girl !!
Hirotaka & Michiko Takahashi
had a baby girl on April 1.
They named her Sachie（咲智恵）.

Congratulations !

60 th
On Feb 27, ICRR Mozumi groupcelebrated Masatake Ohashi forhis 60th. Congratulations!!

15

KAGRA Scientific Congress Newsletter No. 72020 APRIL 17

In the book, “Physics 2020”, an annual review of physics research for general,
Yuta Michimura wrote an article on KAGRA.
Maruzen Publishing Co. (2020/Jan 24). ISBN: 978-4621304860, 2090 JPY.

Kagaku (Science) magazine from Iwanami
Publishing Co. featured “Mystery of Black Holesand Gravitational Wave Astronomy” in theirFebruary 2020 issue.
From our colleagues, Takaaki Kajita, Masatake
Ohashi, Tomoya Kinugawa, Takahiro Tanaka,
Kohei Inayoshi contributed with each article.
1400 JPY.

Takaaki Kajita has contributed not only an article on KAGRA but also acolumn entitled "Reconsider science policy in Japan which has reduced thenumber of students and papers from the field of education and research."(教育・研究の現場から学生と論文を減らしてきた“改革”を考え直せ)

Latest ICRR NEWS features KAGRA’s observation run.

Handbook of Astrophysics, ed. by F. Takahara, M. Ie, H. Kodama and T.
Takahashi (Asakura Publishing Co., 2020 Feb.), 912 pages, A5 size,
ISBN978-4-254-13127-7, 22000 JPY.
We see contributions of Nobuyuki Kanda, Kazunori Kohri, Hideyuki
Tagoshi, and Jun’ichi Yokoyama.

Yuta Michimura commented on his
proposal of detection of dark matter using
KAGRA in Nikkei Newspaper, December
20, 2019.

Hisaaki Shinkai commented on timemachine in the section of cool science in
Nikkei Business magazine (Mar 22, 2020).
He also commented on KAGRA briefly how
unexpected results may come to science.

16

KAGRA Scientific Congress Newsletter No. 72020 APRIL 17

Next chance of Face-to-Face
U. Toyama group booked the Kuroda hall August 20 (Thur.), 21 (Fri.), & 22 (Sat.) for our F2F meeting thissummer. After that, many universities has changed the semester period due to COVID-19, and this schedule
will overlap with the semester for many people, including of U Toyama, unexpectedly. The KSC board received
requests to re-schedule the date, however it turned out that there is no alternative vacancy of the hall.
Therefore, we keep the original schedule.
Please manage your schedule, and let’s enjoy beautiful food in Toyama together again.

KAGRA MEETING SCHEDULE
Mark your calendar now for the following meetings.
KAGRA telecon alternative to Face-to-Face in April, May 27 & 28, 2020.
(alternative to F2F April. refer the wiki page for access information and schedule).
The 25th KAGRA Face-to-Face meeting at U. Toyama, August 20-22, 2020.
(see above article)
LIGO-Virgo-KAGRA collaboration meeting at Cardiff, UK, September 14-17, 2020.
The 26th KAGRA Face-to-Face meeting, at National Central U., Taiwan, December 17 & 18, 2020.
The 7th KAGRA International Workshop, at National Central U., Taiwan, December 18-20, 2020.
(see article in p.11)
LIGO-Virgo-KAGRA collaboration meeting at Lake Geneva, WI, USA (?), March 22-26?, 2021.
The 8th KAGRA International Workshop, at KASI, Daejeon, Korea, sometime 2021
The 9th KAGRA International Workshop, at National Astronomical Observatory, Beijing (NAOC),
China, sometime 2021

RECENT KAGRA STATUS TALKS SEE [JGW-E1605649] FOR THE LIST.
meeting/conferences

speaker

JGWdocCRC Town Meeting at Osaka, Japan

Dec. 2019

Takayuki Tomaru[JGW-G1911136]

CRC Town Meeting at Osaka, Japan

Dec. 2019

Sadakazu Haino[JGW-G1910901]

the 32th Rironkon Symposium, NAOJ, Japan

Dec. 2019

Yuta Michimura[JGW-G1911123]

the 2nd Toyama international symposium on“Physics at the Cosmic Frontier”

Mar. 2020

Matteo Leonardi

the 3rd World Summit on Exploring the Dark
Side of the Universe (remote)Mar. 2020

Keiko Kokeyama

LVK 2020 March meeting (telecon)

Mar. 2020

Hisaaki Shinkai

JPS meeting, Nagoya, Japan (slide only)

Mar. 2020

Masayuki Nakano

17[JGW-G1911158]

KAGRA Scientific Congress Newsletter No. 72020 APRIL 17

KAGRA COLLABORATION ARTICLESProspects for Observing and Localizing Gravitational-Wave Transients with Advanced LIGO, Advanced Virgo and
KAGRA (aka. scenario paper)
Abbott, B. P. et al. (KAGRA Collaboration, LIGO Scientific Collaboration, and Virgo Collaboration)[arXiv:1304.0670] https://arxiv.org/abs/1304.0670 updated Jan 14, 2020
Application of the independent component analysis to the iKAGRA data
KAGRA collaboration (Author List 2015 + 2018)
accepted for publication in PTEP (2020)[arXiv:1908.03013] https://arxiv.org/abs/1908.3013
Overview of KAGRA : KAGRA science
KAGRA collaboration (Author List 2018 + alpha + 2019 if ready) [JGW-P2011478]
submitted to PTEP
Overview of KAGRA : Detector design and construction history
KAGRA collaboration (Author List 2018 + 2019 if ready) [JGW-P2011614]
will be submitted to PTEP after the internal review is over

Collaborator-list managers made their mailing address kagraros@icrr.u-tokyo.ac.jp; ros from a roster.
If your affiliation address (or email) changes: Contact to kagraros@icrr.u-tokyo.ac.jp
If your group has new members: Contact to kagraros@icrr.u-tokyo.ac.jp
If you have a nice photo: Let the KSC Newsletter share them.
If your neighbor is planning to join KAGRA collaboration: Please suggest to check out our wiki FAQ
http://gwwiki.icrr.u-tokyo.ac.jp/JGWwiki/KAGRA/KSC/FAQ

FROM EDITORS
We appreciate many contributors again for this issue.
We are always calling editorial volunteers, and we also want your posts and/or leaks of
information.
Please send your inquiries the current editorial staff.
Hisaaki Shinkai (OIT) hisaaki.shinkai at oit.ac.jp
Ayaka Shoda (NAOJ) ayaka.shoda at nao.ac.jp
Yoshihisa Obayashi (ICRR) ooba at icrr.u-tokyo.ac.jp
Kentaro Komori (MIT) kentarok_at_mit.edu
Quynh Lan Nguyen (UND) lnguyen3_at_nd.edu

With the faith and hope that Virgin Mary always with us
and bless us to overcome the coronavirus pandemic.

KSC Newsletter backnumbers
this issue[JGW-L1911619]
https://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/DocDB/ShowDocument?docid=11619
No. 6 (2019/12)[JGW-L1911020]https://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/DocDB/ShowDocument?docid=11020
No. 5 (2019/8)[JGW-L1910543]https://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/DocDB/ShowDocument?docid=10543
No. 4 (2019/4)[JGW-L1910057]https://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/DocDB/ShowDocument?docid=10057
No. 3 (2018/12)[JGW-M1809350]https://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/DocDB/ShowDocument?docid=9350
No. 2 (2018/8)[JGW-L1808559] https://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/DocDB/ShowDocument?docid=8559
No. 1 (2018/4)[JGW-L1808122] https://gwdoc.icrr.u-tokyo.ac.jp/cgi-bin/DocDB/ShowDocument?docid=8122

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